It's a Via Dolorosa that leads to court

A t an Oscars party earlier this year Sir Tom Stoppard was asked about a lawsuit that accuses him of stealing the plot of Shakespeare in Love from a novel called The Quality of Mercy. "I've never heard of it," Stoppard said. "But I regard any lawsuit as an accolade."

In New York last week Sir David Hare failed to win a Tony award for The Judas Kiss, Amy's View or Via Dolorosa. But the last of these three plays has now received its own back-handed tribute. Steven Greenstein, a Los Angeles-based actor and playwright, is seeking unspecified damages in the Federal District Court in Manhattan against The Royal Court, the original producers of Via Dolorosa.

In late 1996, Greenstein, aged 39, submitted a play called Voices from the Holy ... And Not So Holy Land to the Royal Court. The suit accuses that theatre of commissioning Sir David to write a play that "incorporated central elements, ideas, themes, structures and even some dialogue from the plaintiff's play", which has since been performed in small theatres in San Diego, Los Angeles, New Jersey and Antwerp.

Both plays are one-man monologues which explore the Arab-Israeli conflict. Both plays are performed by the playwrights themselves, who take on the roles of the people they meet. Both plays begin outside Israel and examine the Middle East from a visitor's perspective. Neil Adleman, from Harbottle and Lewis, media and entertainment lawyers, says: "It's an interesting one: having a go at the company for commissioning something similar rather than having a punt at the playwright himself."

The Royal Court has records of its correspondence with David Hare. It also keeps a log of when all unsolicited scripts arrive. The Hare correspondence predates the arrival of Greenstein's play. "The idea that Stephen Daldry used the idea in commissioning David Hare is entirely false," says Vikki Heywood, the executive director of the Royal Court. "The case has no merit, and we are convinced that it will be dismissed."

The issue has wider implications for the Royal Court. The costs are already damaging. "It is alarming that by exposing our work to the American litigious environment," says Heywood, "we have fallen foul of something which I understand to be fairly common practice now in the USA. I was in New York last weekend and had several conversations with American producers who assured me that they will no longer read unsolicited scripts." This is a blow to the Court's open play-reading policy. "We undertake to read any script sent to us by any writer. In America this service is almost unheard of because it is too dangerous in terms of copyright litigation."

But the law in this area is unpredictable. In this country the Copyright, Designs and Patents Act 1988 says copyright doesn't protect abstract concepts, ideas or information. It can protect only the recorded expression of abstract concepts, ideas or information. Proving this becomes a question of "fact and degree". New York is even stricter at making this distinction.

To be successful, Greenstein would need to prove that his script had almost certainly been read by one of the people involved either in commissioning Hare, or in subsequently discussing the project with him - more specifically, the theatre's then artistic director, Stephen Daldry. "It is not enough," says Adleman, "to say that the play was in the same building." Greenstein would then need to prove that Hare's play showed evidence of substantial borrowing. "He would have had to have copied a key element, a detailed collection of ideas or pattern of incidents."

The law on copyright balances two ideas. One is to protect the product of people's skill, creativity, labour or time. The other is to recognise that you cannot claim ownership to general concepts. Everyone nicks something. After all, there are famously only half a dozen plots. Out of his 38 plays Shakespeare invented three storylines of his own. Literary theft even has its staunch defenders. It was T S Eliot, in his essay on the Jacobean playwright Philip Massinger, who wrote: "Immature poets imitate; mature poets steal ..."

Taking legal action in this area is expensive and risky, so most cases are settled out of court. The result is that very few precedents or principles have been established for playwrights. There are lots of examples to be drawn from cases involving computers games, pop sampling or TV formats - when another law, the law of confidence, has been used against people who have run off with an idea that had been broached to them in confidence.

With copyright law there is the further complication that it is all about protecting the written word. As plays become less and less text-based, new problems arise. How would a company such as Theatre de Complicite protect the distinctive elements of its production of The Street of Crocodiles? These are only notionally captured by dialogue and stage directions. It is yet to be seen in this country how an actor or director might copyright their performance or production.

And Via Dolorosa isn't just a play. It is an event. David Hare appears in a David Hare play talking about David Hare. His presence is its defining aspect. It would be fascinating to hear lawyers for the plaintiff argue that so distinctive a creation could be a substantial borrowing from a script by a (till now) relatively unknown Los Angeles actor. I'd get tickets to hear someone try to put that case.